1. Field of the Invention
This invention relates to apparatus for making enlargements from microfilm.
2. Description of the Prior Art
The practice of using reader-printer apparatus comprising the combination of a copying system and a reader is quite popular. One known reader-printer apparatus is the KODAK IMT-350 Microimage Terminal. This reader-printer apparatus includes means for quickly retrieving a desired image frame stored on a 16 mm microfilm and an optical system for imaging the microfilm image onto a screen during a viewing mode. An electrophotographic reproduction engine is also provided for reproducing enlargements of the microfilm image onto copy sheets such as plain paper. An advantageous feature of this apparatus is that there is the capability for an operator to control reproduction to a selected portion of the image that appears on the viewing screen. Thus, if an image of a projected image frame is of relatively short length it is quite likely that at least a portion of a second image frame will also appear on the screen. The operator can select an image length to be printed by using indicia associated with the screen and suitable buttons to have the reproduction process controlled so that only the image length segment selected for reproduction is reproduced and thereby preclude the reproduction of information on adjacent image frames. While this apparatus works well, a problem with it is that where there are a large number of image frames to be reproduced, extra operator time will be required to designate the image length to be reproduced for each frame.
U.S. Pat. No. 4,623,935 describes an apparatus and method for electronically scanning an image frame on a microfilm for transmission of the signals used in reproducing the image for copying same. The apparatus scans the image frame and detects the black borders surrounding same. The apparatus then electronically deletes the transmission of signals reproducing the black borders to provide copies without black borders. In this apparatus there is a need for circuitry to perform electronic scanning of an image and its borders as well as circuitry for distinguishing image information from border information.
It is, therefore, an object of the invention to provide apparatus for producing enlargements of images stored on microfilm without having images from more than one image frame appear on an enlargement and without the need for the operator to select the image length to be reproduced for each such frame.
It is a further object of the invention to provide apparatus for producing enlargements of images stored on microfilm without the need for providing of circuitry for electronically erasing border areas of the images.